AsyncLoopThread refreshzk = new AsyncLoopThread(refreshZkActive);
AsyncLoopThread hb = new AsyncLoopThread(heartbeat_fn, false, null,
Thread.MAX_PRIORITY, true);
AsyncLoopThread dr = new AsyncLoopThread(new DrainerRunable(transferQueue, nodeportSocket, taskNodeport));
AsyncLoopThread[] threads = { refreshconn, refreshzk, hb, dr };
return new WorkerShutdown(shutdowntasks, active, nodeportSocket,